Varnish for making enamel and patent leathers.



NrTED STATES PATENT QFFICE HARRY C. MOKAY, OF ESSINGTON, PENNSYLVANIA,ASSIGNOR, BY MESNE ASSIGNMENTS, TO AMERICAN PATENT KID COMPANY, ACORPORATION OF NEW' JERSEY.

VARNISH FOR MAKING ENAMEL AND PATENT LEATHERS.

SPECIFICATION formingpart of Letters Patent No. 704,082,.dated July 8,1902.

Application filed December 29,1900. Serial No. 41,4=61. (No specimens.)

To (0% 2127710722, it may concern:

Be it known thatI, HARRY C. MCKAY,a citizen of the United States,residing at Essington, Delaware county, Pennsylvania, have invented acertain new and useful Varnish for Making Enamel and PatentLeathers,0fwhich the following is a full, clear, and exact description.

My invention relates to a preparatory varnish to be applied to thesurface of a tanned or properly-prepared skin to enable it to receiveand hold any usual finishing varnish commonly applied to form theexterior or enamel surface of enamel and patent leathers. Heretoforepatent and enamel leathers made of calfskins were usually if notentirely enameled on the flesh side of the skin; but other skins, suchas sheep and kid skins, were so enameled on either side, sometimes, butnot always, preceded by a roughening or buffing of the grain-surfacewhen the enamel was ap plied to the grain side of the skin; but oneither kind of skins and no matter how prepared after tanning the enamelheretofore employed formed a stiff surface, more or less lacking inpliability,liable to crack, and otherwise open to many well-knownobjections, and this was due largely to the fact that the enamel varnishwas, in effect, nothing but a thick adhering paste wholly incapable ofhomogeneous union with the fiber of the skin, though less open to thatobjection when applied to the flesh side than when applied to the grainside of the skin. In the making of enamel and patent leathers it hasalways been and still is deemed necessary to apply at least two, andmore frequently three or four, coats of the enamel varnish, sometimesrubbing or roughening with pumice-stone the surface of each coatpreceding the last to give it a more adhesive surface.

I have discovered that if the first varnish applied to the tanned skinbe a compound composed of a drying oil, specifically boiled linseed-oil,and a vehicle of high penetrative and adherent power on such substanceas skin-tissue, specifically a pyroxylin solution thinned with amylacetate that is to say, a thin varnish of high penetrating properties,in which the ingredients employed are of such a character that thevarnish will thoroughly penetrate the grain-surface of the skin andtenaciousl y adhere to the fibers thereofthe ordinary finishing enamelscommonly used in making patent and enamel leathers may be employed toproducea finished leather in which there willbe asubstantial homogeneityin the union of enamel and skin substance to an equal extent, whetherthe enameling be done upon the flesh side or upon the grain side withoutany buffing or roughening of the surface, the employment of mypreparatory varnish, applied as hereinafter described, resulting in anabsence of the usual stiffness commonly inherent in finished patent andenamel leathers with almost complete absence of the common tendency tocrack on the surface and possessing an elasticity and pliability almostequal to common glazed kid and other light-weight leathers.

My preparatory varnish is a true mordant in the sense thatwhen'appliedit is instantly taken up and absorbed by the grain side of the skin,penetrating through the external surface thereof and permeating andadhering to the entire fibrous structure of the grain side,forming onsuch fibrous structure a penetrable film or foundation surface to whichthe external varnish unites or at least attaches itself with remarkabletenacity, practically uniting therewith.

I will now proceed to describe my new preparatory varnish, its essentialingredients,the best mode of compounding the same, and the best mode ofapplying it to the skin-surface.

One (1) quart of linseed -oil, to which a thickening and drying matter,such as onehalf ounce of raw umber, is added, is boiled to theconsistency of fresh mucilage or thick molasses. I thin or reduce thisoil by adding, according to the temperature of the weather, about anequal bulk of amyl acetate or sufficient to give the solution aconsistency of 31 Baum. I next prepare separately two (2) gallons inbulk of a solution composed of, say, sixteen (16) {ounces of guncotton,dissolved in about two (2) gallons of amyl acetate, and that mixturegives the bulk stated when of the consistency of fresh mucilage'ormolasses. Those two solutions are then mixed IOU a goat, kid, or sheepskin is used, and its absorption by or biting effect on thegrain-surface of the tanned skin without any roughening or buffing ofthe latter is almost instantaneous, with the result of forming ahomogeneous union therewith having the properties as described, it beingunderstood also that after the preparatory varnish is thus applied, theskin being stretched upon a frame, it is then put into a drying oven orkiln for several hours, or as long as necessary to thoroughly dry it,the heat of the oven being maintained at about 110 Fahrenheit. Enameland patent leather is then made therefrom by applying any of the knownenamel-varnishes commonly employed as a surface enamel and by the usualdrying methods and means.

Having thus described my invention, what I claim as new, and desire tosecure by Letters Patent, is

1. A preparatory varnish for the purpose described, composed essentiallyof boiled linseed-oil admixed with a solution of guncotton in amylacetate.

2. A mordanting varnish for the purpose described, composed essentiallyof boiled lin-' seed-oil admixed with a solution of guncotton in amylacetate, and a coloring-matter dissolved in methyl alcohol. v

In testimony whereof I have hereunto affixed my signature this 26th dayof Decemher, A. D. 1900. I

v HARRY C. MoKAY. WVitnesses:

ANDREW V. (Rooms, 11. T. FENTON.

